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This signal is from the Pasternack $2.4\textrm{ GHz}$ development kit. The saved signal appears to be the pulsed waveform. It is sampled at $20\textrm{ kHz}$ for $4130$ points. I recorded a background signal, then aimed at a moving target ($\approx 20\textrm{ mph}$ vehicle).
enter image description here My goal is to remove the background clutter and determine the velocity and range of the vehicle from this data. So far I have had very little luck. Here is what I have done:

  1. Get the FFT of background and target signal
  2. Remove the background clutter by subtracting in the frequency domain
  3. Inverse the FFT
  4. Split the signal into $n$ windows
  5. Do the FFT of each and compare to find differences between each window

This method gives me velocities in the $100\textrm{ mph}$ range. I also tried taking the difference between the background max frequency and target max frequency and still have incorrect velocities. Are there any other methods to analyze this data? I feel like the data as provided is useless because of the downsampling and also no time/delay info is included.

A copy of the raw data can be found here. I think the PRF is about $160\textrm{ Hz}$.

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  • $\begingroup$ What exactly is the signal you've recorded? Is it raw receive signal in baseband? On an IF? Is it beat frequency? What bandwidth does Pasternack specify it should have? $\endgroup$ – Marcus Müller May 12 '17 at 6:53
  • $\begingroup$ its the raw receive signal - possibly beat frequency. The manual doesn't specify this info and neither does the program or the output file. I know the transmitted was 2.4GHz and the sampling rate is 20kHz. I assume it would be a beat frequency since its the only way to recover the GHz signal. I'm just not sure how to approach this - the fft has a high DC as well. $\endgroup$ – user19960 May 12 '17 at 23:40

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